Approximately, from the beginning of the opening of the apparatus, the pawl projecting into the barrel retains the inertia block therein. With the barrel driven forwardly, the immobilized inertia block in effect moves backwards relative to the barrel, the space between the rear end of the inertia block and the inner bottom wall of the case decreases and the gases present within this space are compressed by means of the inertia block so as to normally cause the case to be ejected from its housings defined within the barrel and the ring.
However, and more particularly because of residual combustion particles, the ejection ring which normally follows the barrel during the beginning of its forward movement may be stopped within the barrel holder before it abuts the pawl as a result of the resistance of the particles being greater than the frictional forces of the clip upon the barrel. The result is a relative backward movement of the ejection ring with respect to the barrel whereby the above mentioned space remains too large and is not properly sealed in order to permit the gases to be sufficiently compressed and to therefore be able to properly eject the case.
The present invention aims at overcoming the aforenoted drawback and provides a power tool apparatus characterized by means of a reliable and efficient case ejection or with a perfected ejector.